html, body{
    overflow: hidden;
    margin: 0;padding: 0;
}

.confirm-warning {
    border-color: crimson;
    box-shadow: 
    2px 2px 4px 0 crimson inset,
    -2px -2px 4px 0 crimson inset,
    2px -2px 4px 0 crimson inset,
    -2px 2px 4px 0 crimson inset;
}